Yes there "should" be aftermarket shifters available that are longer , (At least for most models , though I did not find any doing a quick Google search for a 19 450X) , BUT , You could try adjusting the shifter higher , by loosening then removing completely the pinch bolt where it attaches to the spline , noting its location on the spline , pull the shifter out/off , then turning it up one more notch then reinstalling and see if that helps , you can go another if that is not enough but is better than it was , I personally run mine about 2 notches up from level/stock on both my 02 450R and my 06 450X , so that is perfectly common because of thicker boots and should not be a issue with shifting once done ...... If it is still not enough , then get a aftermarket one that is longer and you should be good to go .....
I looked in Ken's parts and did not see a shifter for it , but that does not mean he can't get one ..... you could PM him and ask if he has one that will fit or if he can get a longer shifter for it .....
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